The invention relates to an apparatus on a carding machine for cotton, synthetic fibres and the like, in which at least one flat bar with a flat clothing is present.
In practice, in the case of the flat system of a flat card, the flat bar is set at an angle (what is known as the taper or offset) to the tangential cylinder plane. This has inter alia the following advantages over the central arrangement:
the narrowest spacing of the cylinder is at a defined adjustment edge (heel) which can be emptied out well;
The material gradually enters a tapering gap and is opened/cleaned in an improved manner.
In certain known arrangements the flat clothing, preferably wire hooks, arranged in a strip-form support element is secured to a carrier body of the flat bar, and lies opposite the clothing of a roller, e.g. the cylinder, the spacing between the tip plane of the flat clothing and the tip circle of the cylinder clothing decreases in the direction of rotation of the cylinder, and the tip plane of the flat clothing and a notional surface—arranged parallel to the tangent to the tip circle of the cylinder clothing at the narrowest point—are arranged at an angle β to one another.
In the case of one known apparatus EP 0 866 153 A, a carrier body (profiled member) having a bottom face is present, to which a flexible clothing comprising a carrier layer (base) and hooks embedded therein is secured. The base is adhesively secured to the foot part. The flat bar is guided in its working position (in the main carding zone) such that the tips of the hooks lie in a catchment plane (tip plane) which comprises a very narrow point or very narrow carding line opposite the outer surface of the cylinder. The catchment plane forms an angle β with a notional surface, the notional surface being arranged parallel to the tangent that intersects the outer surface at the above-mentioned narrowest point. To produce the angle β, the flat bar and the carrier body respectively must be designed within an inclination at a corresponding angle, and be both manufactured and mounted at an inclination, i.e. the inclination of the carrier body in relation to the tangent to the outer surface, and hence the angle β, is fixed for each card flat. When the carrier layer with the clothing is exchanged due to wear, the angle β remains the same owing to the parallel arrangement of the top and bottom faces of the carrier layer. With this apparatus, alteration of the angle β or adaptation to changed technical requirements is only possible through a change in the inclination of the carrier body, which is expensive in mechanical engineering terms.